The present invention relates to a new and improved construction of a surgical retaining or holder device for holding a surgical instrument in place, especially although not exclusively wound hooks, which is of the type comprising a holder block serving for the displaceable attachment of the holder device at a stationary object and at least one insert element at which there can be inserted and fixedly clamped the surgical instrument, wherein the holder block and the insert element are coupled with one another by a number of lockable or blockable joints.
In the context of this disclosure the expression "surgical instruments" not only encompasses the aforementioned wound hooks, but also other surgical instruments, such as, for instance, speculars for the most different purposes as well as wound spreaders, magnifying lenses, spatulas, holders for X-ray plates or cassettes and similar instruments, which enable the surgeon to carry out or perform more easily his work.
In U.S. Pat. No. 3,858,578 as well as in German petty Pat. Nos. 6,941,781 and 7,010,461 there have been disclosed to the art such type of surgical retaining or holder devices. With the prior art holder devices there is provided a flexible link arm between the insert element and the holder block. This link arm is composed of a multiplicity of link elements possessing at one end a ball and at the other end a complementary ball socket. The link elements, in turn, are threaded, in the manner of pearls upon a string of pearls, onto a flexible traction element. At the neighborhood of the holder block the traction element is connected with a clamping device (in U.S. Pat. No. 3,858,578 such is constituted by a pneumatic cylinder and in the aforementioned German petty patents there are provided clamping screws), by means of which there can be tightened the traction element, so that the link arm which is composed of practically a multiplicity of ball-and-socket joints which are arranged in a row is caused to assume a rigid structure i.e., can be arrested in any position selected by the surgeon or other user of the device.
In practice it has been found, however, that the state-of-the-art surgical retaining or holder devices are not capable of positionally fixing larger wound hooks with adequate retention force, such as for instance would be necessary when performing more complicated operations, such as for thorax or abdominal surgery, in order to fix with the requisite security the edges of the wound in position. This is not overly surprising if it is recognized that with a single traction element (irrespective of its unavoidable elongation) it is hardly possible to increase the friction at each of the multiplicity of ball-and-socket joints to such an extent that the link arm can be in fact transformed into a rigid structure. This difficulty in attaining a sufficient retention force with the heretofore known holder devices has also resulted in restricting their practical use in surgery to those instances where the surgeon is working in a relatively small operating zone, for instance, for neurological surgery.
Additionally, the prior art surgical retaining or holder devices are associated with a further disadvantage inasmuch as the end of the link arm supporting the insert element, upon tightening of the traction element, has the tendency of slightly shifting out of the position selected by the surgeon. Finally, it is also to be mentioned that the multi-element link arm constitutes a structure which can only be sterilized with considerable effort.